E. ROLE OF CORE COMPONENT IN PROGRAM PROJECT This core is essential to the continuing leadership and management of the program project and, in addition, the statistical data analysis. The core provides leadership for the program project and facilitates the integration of the numerous other related studies that draw on the Nurses'Health Study database. The Core coordinates the annual meeting of the external advisory committee and the regular meeting of investigators on this program project and the interchange between these investigators and the other investigators working on related projects. Statisticians draw on methods developed in Project 4 for analyses within projects 1, 2, and 3, as noted in the specific projects. The Core staff also processes the requests and access to data from outside users, coordinating these activities with investigators on the Nurses'Health Study who have expertise in the areas of interest to the outside users. The close work among the investigators from various projects maximizes efficiency, provides important input from a variety of sources, prevents duplication of effort and results in a more coherent presentation of results across endpoints. The underlying goal of all the projects is the same: to better understand ways of preventing cancer. This goal can be optimally achieved within the context of a program project.